Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Search Results

Now showing 1 - 10 of 2744
  • Article
    A Capsular Polysaccharide from a Healthy Human Microbiota Member Activates a Lag-3-NK Cell Axis to Restrain Colon Cancer and Augment Immunotherapy
    (Cell Press, 2025) Weis, Allison M.; Tang, William W.; Stephen-Victor, Emmanuel; Bell, Rickesha; Brown, D. Garrett; Round, June L.
    Colorectal cancer (CRC) is increasing globally, making identification of preventative measures necessary. Transplantation of the microbiota from CRC and non-CRC patients into mice demonstrates that non-diseased individuals possess organisms that reduce tumor formation and highlights Bacteriodes uniformis as protective. B. uniformis is reduced in humans with CRC, and proactive treatment with B. uniformis slows tumor growth in mice. Natural killer (NK) cells, but not T cells, are required for B. uniformis-mediated protection. CRC is recalcitrant to immunotherapies; however, addition of B. uniformis restores response to alpha-CTLA-4 treatment in an NK cell-dependent manner. We report that high Lag-3 expression is associated with greater survival in CRC patients and that B. uniformis-mediated protection is reliant on Lag-3 in innate cells. Induction of NK cell activity and reduced tumor growth is dependent on a specific B. uniformis capsular polysaccharide. Thus, healthy individuals possess tumor suppressor microbes that prevent cancer development and can be harnessed therapeutically.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Reconfigurable Polyhedral Mechanisms Using Scissor-Like Elements with Cantellation Transformation Between Dual Geometries
    (Pergamon-Elsevier Science Ltd, 2025) Liao, Yuan; Kiper, Gokhan; Krishnan, Sudarshan
    Deployable polyhedron mechanisms (DPMs) have garnered significant interest in architecture, aerospace, and robotics, where reconfigurable and space-efficient structures are crucial. This paper presents a tangential design method for DPMs using scissor-like elements (SLEs). Scissor units are placed along the edges of an equilateral polyhedron, tangential to its midsphere. This method enables the mechanisms to transform between a polyhedron and its dual, following the cantellation operation. Using screw theory, the kinematic properties of these mechanisms are analyzed. Results show that the DPMs exhibit 1-degree of freedom (DOF) under normal conditions and gain additional DOFs at multifurcation points, allowing for reconfigurable motion modes. Physical models based on various geometries, including Platonic, Archimedean, Johnson, and Catalan solids, help to validate the method's feasibility. Observations indicate that this method is only applicable to equilateral supporting polyhedra. The transformability and reconfigurability observed in these mechanisms demonstrate the potential of this approach for applications in architecture, aerospace, and robotics.
  • Article
    Making Hierarchically Aware Decisions on Short Findings for Automatic Summarisation
    (Elsevier, 2025) Inan, Emrah
    An impression in a typical radiology report emphasises critical information by providing a conclusion and reasoning based on the findings. However, the findings and impression sections of these reports generally contain brief texts, as they highlight crucial observations derived from the clinical radiograph. In this scenario, abstractive summarisation models often experience a degradation in performance when generating short impressions. To address this challenge in the summarisation task, our work proposes a method that combines well-known fine-tuned text classification and abstractive summarisation language models. Since fine-tuning a language model requires an extensive, well-defined training dataset and is a time-consuming task dependent on high GPU resources, we employ prompt engineering, which uses prompt templates to programme language models and improve their performance. Our method first predicts whether the given findings text is normal or abnormal by leveraging a fine-tuned language model. Then, we apply a radiology-specific BART model to generate the summary for abnormal findings. In the zero-shot setting, our method achieves remarkable results compared to existing approaches on a real-world dataset. In particular, our method achieves scores of 37.43 for ROUGE-1, 21.72 for ROUGE-2, and 35.52 for ROUGE-L.
  • Article
    A Critical Analysis of Pulverization Mechanism During Hydrogen Decrepitation of End-Of Ndfeb Magnets
    (Elsevier Science Sa, 2025) Habibzadeh, Alireza; Gokelma, Mertol
    Given the increasing demand and limited availability of rare earth elements (REEs), innovative solutions are critical to managing supply risks. Recycling is a key strategy in mitigating these risks, particularly for NdFeB magnets, which consume a large portion of REEs. Among the various recycling processes, hydrogen decrepitation (HD) has gained popularity due to its efficiency in producing fine powders for magnet-to-magnet recycling. While the HD mechanism is commonly attributed to hydride formation in the Nd-rich grain boundary phase, this study presents new findings that challenge this assumption. Through the hydrogenation of End-of-Life (EoL) NdFeB magnets at temperatures ranging from 25 to 400 & ring;C, the results indicate that the primary mechanism of pulverization arises from hydride formation in the Nd2Fe14B matrix rather than in the Nd-rich phase, especially at low temperatures where NdH2 formation is kinetically unfavorable. This revised mechanism was supported by evidence from X-ray diffraction, BSE and SE-SEM imaging, particle size analysis, diffusion modeling, and stress analysis.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    A Novel Hybrid Thin Jacketing Method for Seismic Retrofitting of Substandard Reinforced Concrete Columns
    (Elsevier Ltd, 2025) Narlitepe, Furkan; Kian, Nima; Demir, Ugur; Demir, Cem; Ilki, Alper
    This paper introduces a novel hybrid thin jacketing method for seismic strengthening of substandard reinforced concrete (RC) columns for which structural repair mortar along with carbon fiber reinforced polymer (CFRP) and longitudinal steel bars are utilized. The method involves three application phases comprising a) removing the cover concrete, b) re-forming the cover concrete with structural repair mortar just after installing extra longitudinal steel bars c) transverse wrapping of CFRP sheets. The effect of using different types of structural repair mortar and its application process are other test parameters taken into account in this study. To evaluate the efficacy of the proposed method, a comprehensive experimental program was conducted, consisting of six largescale RC column specimens with square and rectangular cross-sections. For all of the specimens tested under a simultaneous constant axial load and reversed cyclic lateral loading, three main properties representing existing substandard RC columns such as a) insufficient transverse reinforcement, b) high axial load ratio (0.75) and, c) relatively high shear force corresponding to moment capacity to shear capacity ratios between 0.60 and 0.80, were considered. The responses of specimens were specified in terms of the lateral load-displacement curves, stiffness variation, ductility ratios, damage progression, and energy dissipation. The experimental results demonstrated that in case the retrofitting method is properly applied, the strengthened columns exhibit satisfactory performance in terms of strength and ductility with a remarkable improvement with respect to the substandard columns. Furthermore, a numerical study was conducted to validate the experimental results by using the OpenSees framework.
  • Article
    Influence of Fluorine on Structural and Electrical Properties of VO2 Thin Films Deposited by Magnetron Sputtering
    (Elsevier Ltd, 2025) Akyurek, Bora; Cantas, Ayten; Demirhan, Yasemin; Ozyuzer, Lutfi; Aygun, Gulnur
    This study investigates whether fluorine-based thermal gel used during electrical measurements of vanadium oxide (VO2) films influences the structural, morphological, or compositional integrity of the films. High-quality VO2 films with a resistance ratio change of about 10(4) for metal-insulator transition were deposited by magnetron sputtering. During electrical characterization, VO2 film was heated from room temperature to similar to 370 K with a fluorine-based thermal gel usage to achieve better heat contact between the film and substrate holder. Structural and chemical properties were assessed through XRD, Raman, XPS, SEM, and energy dispersive spectroscopy imaging. XRD revealed diffraction peaks consistent with monoclinic VO2 confirming that the crystal lattice remains the same although fluorine based thermal gel was used. Raman spectra exhibited vibrational modes indicating that the phonon structure of VO2 was preserved despite fluorine gel usage. XPS results showed only a minor F 1s signal (2.8%) limited only to the film surface. SEM and EDS analyses further confirmed that surface morphology and elemental composition remained belonging to VO2 film. These findings demonstrate that the usage of fluorine-based thermal gel results in only a minimal surface interaction, thereby preserving intrinsic material properties of VO2 and supporting a potential usage for future device fabrication applications.
  • Article
    Citation - WoS: 15
    Search for Supersymmetry in pp Collisions at √s=7 TeV in Events With a Single Lepton, Jets, and Missing Transverse Momentum
    (Springer, 2013) Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Swanson, J.
    Results are reported from a search for new physics processes in events containing a single isolated high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The analysis is based on a 4.98 fb(-1) sample of proton-proton collisions at a center-of-mass energy of 7 TeV, obtained with the CMS detector at the LHC. Three separate background estimation methods, each relying primarily on control samples in the data, are applied to a range of signal regions, providing complementary approaches for estimating the background yields. The observed yields are consistent with the predicted standard model backgrounds. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model, as well as on cross sections for simplified models, which provide a generic description of the production and decay of new particles in specific, topology based final states.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 2
    Elastic and Anelastic Behavior Associated With Structural Transitions in CsPbBr3
    (Amer Chemical Soc, 2025) Luo, Pingjing; He, Zhengwang; Yang, Dexin; Aktas, Oktay; Ding, Xiangdong; Zhang, Xuefeng
    Strain coupling and relaxation dynamics critically influence the photovoltaic and photoluminescent performances of metal halide perovskites. Here, resonant ultrasound spectroscopy is employed to study the elastic and anelastic properties associated with the octahedral tilting transitions in the optoelectronic semiconductor CsPbBr3 over the temperature range 303-468 K. The cubic-to-tetragonal transition near 405 K is marked by pronounced elastic softening accompanied by a sharp increase in acoustic loss. High anelastic loss below this transition reveals the presence of mobile ferroelastic twin walls that become pinned by lead vacancies at a temperature interval near 380 K in the tetragonal phase. The elastic softening in the cubic phase is strongly correlated to dynamic effects such as the local polar fluctuations. This local disordered effect is further verified by the anomalously high attenuation in the orthorhombic structure, in which the ferroelastic twin walls might become mobile.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Experimental Integration of Stone Topologies To the Simplified Micro-Modeling for the Seismic Response of Masonry Walls: a Novel Insight
    (Springer Heidelberg, 2025) Demir, Ugur
    This study aims to explore the impact of stone typologies on the in-plane seismic behavior of stone masonry buildings. The present study aims to quantify the strength and deformability parameters such as lateral load capacity, ductility, energy dissipation capacity and stiffness degradation of frequently used sandstone and limestone masonry, which will intentionally contribute to the core body of knowledge on their original structural design, seismic safety evaluation and intervention design. The innovative aspect of this research lies in the holistic methodology that integrates field surveys to classify local stone masonry units, experimental characterization of the chemical and mechanical properties of these units to capture variability, and finite element modeling of the in-plane cyclic behavior of stone masonry walls using experimental data. A novel simplified micro-modeling approach is implemented within a standard finite element software, eliminating the need for user-defined subroutines. This approach significantly reduces computational efforts compared to conventional methods, making it particularly suitable for analyzing large-scale stone masonry structures. The study investigates the impact of chemical composition (sandstone or limestone), applied axial stress (0.25 MPa, 0.50 MPa, or 1 MPa), and wall aspect ratios (height-to-length ratios of 1.0 or 1.5) on wall performance. The modeling approach is validated against experimental results from the literature, demonstrating good agreement. Finally, the study assesses wall performance in terms of deformation limits in current seismic codes. The findings provide critical insights for developing innovative design strategies to enhance the structural integrity of stone masonry walls and improve the seismic assessment of existing structures.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 1
    A Novel Framework for Droplet/Particle Size Distribution in Suspension Polymerization Using Physics-Informed Neural Network (PINN)
    (Elsevier Science Sa, 2025) Turan, Meltem; Dutta, Abhishek
    A Machine Learning (ML) based neural network can capture the complex evolution of polymer chain distributions, accounting for factors such as initiation, propagation, and termination steps in a suspension polymerization process, by integrating stagewise molar balance model (MBM) and population balance model (PBM) with Physics-Informed Neural Network (PINN). The integrated PINN framework is proposed to efficiently solve these equations, incorporating known physical laws as constraints and minimizing errors in both the distribution and dynamics of the polymer chains. By optimizing the neural network parameters such as weight matrices and bias vector, the model reproduces the moments of the polymer molecular weight distribution in close alignment with numerical solutions, and it generates population balance solutions that exhibit excellent agreement with their analytical counterparts. Sensitivity analyses for the depth of the neural network architecture to quantify how structural choices affect model fidelity has been performed. The resulting MBM-PINN and PBM-PINN integrated framework demonstrates robustness and versatility in accurately capturing (96-97%) droplet/particle dynamics. The proposed methodology has the capability to provide a powerful tool for faster and scalable simulations of polymerization reactions, enabling better prediction of product properties which could be used for optimizing reaction conditions in industrial applications.